I suggest you first see a Psychiatrist. If you are diagnosed with some of these disorders, and you need medicines, a Psychiatrist will be able to prescribe you medicines. A psychiatrist will also be able to help you decide if you need psychotherapy or any form of behavior therapy.
Some psychiatrists are qualified psychotherapists themselves. Others can guide you to a psychologist or a therapist.
There is a discussion on the difference between a psychiatrist and a psychologist -
You may post any more queries regarding the difference on that thread.
Hope you find answers to your questions. Please post any more thoughts you might want to share.
Abhijeet Deshmukh, MD